Sample-half-inserted quantum interferometer

Authors:Wei Li, Tao Xie, Yu-Hang Luo, Kang Zheng, Meiyu Peng, Hui Yang, Chunling Ding, Chen-Zhi Yuan, Omar S. Magana-Loaiza, Keyu Xia, Ryosuke Shimizu, Hui Jing, Chenglong You, Rui-Bo Jin

Abstract:Quantum technologies have been widely recognized as unprecedented opportunities for ultra-high precision metrology. As a celebrated example in modern quantum optics, the Hong-Ou-Mandel (HOM) interferometer is well-known for enabling temporal resolutions on the attosecond scale. However, the relatively low Fisher information per trial in ordinary HOM measurements typically necessitates tens of thousands of repetitions to achieve such precision. Here, we propose and demonstrate a sample-half-inserted HOM (SHOM) interferometer, which enhances the Fisher information by five orders of magnitude in a single interference event. By introducing an asymmetric photon-sample interaction, the SHOM configuration produces a distinctive dip-bump-dip interference structure, converting what was previously viewed as an artifact into a helpful metrological resource. Experimentally, we measured the optical path difference with an average precision of 4.09 nm (13.63 as) and an average accuracy of 1.22 nm (4.07 as) using $O(10^7)$ photons. Our results establish SHOM interferometry as an efficient phase-insensitive approach, not only paving the way toward practical quantum-enhanced thickness measurement for transparent materials, but also serving as an elegant strategy to improve the performance of various quantum devices.

arXiv:2608.03622 [quant-ph]

(or arXiv:2608.03622v1 [quant-ph] for this version)

https://doi.org/10.48550/arXiv.2608.03622 arXiv-issued DOI via DataCite (pending registration)

https://doi.org/10.1103/hldy-gmnn DOI(s) linking to related resources